The present invention relates to a percutaneous access device and, in particular, to a percutaneous access device having self-sealing and aseptic characteristics.
In the practice of medicine, it is frequently necessary to introduce catheters or other tubular devices into the body and either rotate, push in or pull out the device to adjust the position of the intracorporeal end during the therapeutic or diagnostic procedure. One example is the insertion of vascular access catheters within the heart to access its functional condition. Inherent to such procedure, however, is the risk of trauma to the tissue at the skin interface with the device, of bacterial contamination caused by introduction of the catheter from the non-sterile environment outside the body, and of leakage.
Valves are used in certain catheter applications to prevent leakage via back-flow or reflux. In certain medical applications such as the vascular access applications alluded to above, the valve function is critical to patient health. For example, in vascular access and, in particular, in the use of heart flow diagnostic and pacing catheters, a sheath introducer is used to access the vascular system. The required diagnostic catheter is then placed through the lumen of the sheath introducer into the desired position within the heart. The sheath introducer contains a valve through which the diagnostic catheter passes, and prevents blood from leaking out and air embolisms from entering the patient should the patient sit up quickly. The valve should ideally perform these prophylactic functions both with and without the intraluminal catheter in place. However, because a relatively large bore catheter must pass through the valve, the valve must have a large opening, making sealing of the valve more difficult. In addition, the valve must work at the relatively low pressures associated with vascular physiology.
In addition to fluid and gas sealing properties, the valve should ideally provide an aseptic seal. During repositioning of the catheter, increasing the internal length of the catheter forces a segment previously exposed to the environment and bacterially contaminated into the blood stream.
To our knowledge, previously, there has not been available a device of simple construction which provides effective sealing and resealing functions for vascular access nor, in particular, a device which combines effective sealing and resealing functions as well as anti-microbial and wiping functions.